Unlike sales and marketing, public relations is often a grey area for many small business owners. It’s often not until a respected advisor or board speaks to the merit of PR—or, worse, until a crisis hits—that they’ll make the decision to investigate a firm to help propel a product or service launch (or to do damage control).

While PR can be a cost-effective way to gain public awareness and third-party credibility for your business, it needs to be implemented strategically. Not all PR campaigns stick, and of those that do, not all help small businesses with their end objective.

If you are considering bringing on PR to help position your company in a positive light, or to grow your business, here are five common mistakes you will want to avoid:

1. Waiting too long (or starting too early)

In a marketing plan that embodies branding, advertising and public relations, entrepreneurs often wait to enlist PR help until just before a product or service is going to launch. This is primarily because they are looking for media relations services, forgetting about the value a PR firm can bring from a creative perspective. At this stage it is usually too late for a PR professional to offer the creative ideas that might make your launch more newsworthy.

For instance: a real estate development targeting young couples may want to consider adding his and hers sinks or closets to create more of a story around its target demographic. If a PR professional is brought in just before sales launch, ideas such as these—which make the product or service more newsworthy—often can’t be executed on.

At the same time, many small businesses bring on PR support in the early stages—and want immediate results. That can be a big mistake. If you are launching an app, for instance, it’s important to have all the bugs worked out in your beta testing, to have feedback from focus groups and to be 100% assured that the technology you are launching will stand up to critique before you promote it.

The best practice is to bring on a PR professional at the conceptual stage. Have a strategy in place and then wait on executing until you are absolutely confident in what you are launching.

2. Letting PR replace your salesforce

A clever media campaign can absolutely generate sales leads, but it cannot replace the sales arm of your business. The two can and should compliment each other. Your sales team should be used to determine market price, lead conversion, promotions, and strategies that will appeal to the end business or consumer. Your PR team can determine the best media outlets to reach your target demographic, the messages that will both stick with media and compliment your sales approach, and the best way to time their campaigns with your promotions.

3. Investing in PR and PR alone

It’s never good to put all your eggs in one basket. If you invest your entire marketing budget into PR, you might be disappointed with the results.

PR results can never be guaranteed because you are relying on a third party (the media) to take an interest in an aspect of your business. A savvy PR pro will ensure the angles being pitched compliment your business objectives, but it is important you have guaranteed message channels (such as pay-per-click ads, direct mailers or SEO) in place to guarantee you’re hitting your demographic with your message.

If you’re unsure how much to spend on PR, start by alotting 35% of your existing marketing budget and applying it towards it. If you find this to be effective, you can always increase your spend.

4. Peddling sales pitches, not stories

A good PR practitioner will pitch media outlets a story, not a product. Don’t expect your PR team to go to press with the same messaging used in your promotions or advertising material—editors and producers will balk. Allow your team to get creative and dig for human-interest angles or thought-leader stories that can greatly compliment your end objective.

Editorial teams need to bring value to their readers by offering thought-provoking articles and news segments. Take some time to learn how newsrooms function, and you will become a better conduit for your PR team.

5. Taking an ad-hoc approach

Don’t think of PR as a one-time investment. As fast as you can gain momentum in the press, you can lose it if you don’t have a long-term strategy in place. Just like marketing, PR can have seasonal peaks and valleys. For instance, if you’re running an online clothing store, you’ll want to start pitching holiday gift guides in the summer, and spring fashion tips in the winter as most fashion magazines publish three months out. It’s a good idea to have an annual plan in place that outlines your campaigns.

That said, you shouldn’t be a slave to the plan. As things arise unexpectedly in the media, you may want to undertake “issues hijacking,” the act of adding your thought leadership to a trend that is being heavily reported on. This requires nimbleness and excellent judgement, but when managed well, these stories can get a lot of traction.

As you make strides with the media by pitching them content that is complimentary to their audience, eventually they may start coming to you to be part of features or to comment on topics that are fitting. And that’s when you’ll see your PR investment really take off.